This invention pertains to small gasoline engines and particularly to apparatus to force closure of the fuel supply valve to cause the engine to stop.
In the typical small gasoline engine, a manually activated switch is provided on the engine body which grounds the magneto of the engine when the user wishes to stop the engine from running. The engine is also equipped with a manually operable valve which may be activated to close the fuel line leading from the fuel reservoir to the engine fuel intake. When a small internal combustion engine is to be moved, it is especially advisable to close the fuel valve to prevent gasoline from draining into the engine as the engine is jostled and moved about, leading to overload of the intake valve of the carburetor and permitting gasoline to enter the combustion chamber. Gasoline in the combustion chamber when the engine is not running can cause delubrication of parts of the engine, namely the piston rings and cylinder wall. Manuals for small engines often carry instructions for the user to close the fuel supply valve when the engine is not running especially if it is to be moved, but many users pay little heed to these instructions, instead merely killing the engine and proceeding to move the equipment. As a result, lawn mowers, pressure washers, cement finishing equipment, and many other transportable devices powered by gasoline engines are transported from worksite to worksite with their fuel supply valves open, allowing gasoline to enter the engine eventually causing premature failure of the engine components. The loss of engines due to premature failure is a common and expensive problem which could be avoided with proper precautions or a system which would require closure of the fuel supply valve when the engine is stopped.